Database connection resolves itself; can't login to admin

Hello, Brandon, & welcome to the WordPress support forum. Do you perchance have access to the server error logs? This might tell us a great deal. Another thing you might consider doing is to *briefly* define wp-debug to false in order to see if there are any errors being thrown there. You’ll likely see them when you go to the site homepage. Please do turn this off as soon as you’ve obtained the information you need, though, as the security hole it creates makes the grand canyon look like a child’s sandbox lol.

You don’t tell us if this is a single or multisite install. You also don’t provide a site url, which can be of immense help when attempting to help someone troubleshoot these sorts of problems. Nor do you state what type of server you’re running or the version of your OS, which can also help when giving instructions.

Lastly, you might try running a mysql check/repair utility (it’s usually better to shut down the server first) to repair any corruption of the database that may have occurred.

Let us know how this goes, won’t you? & feel free to paste error log entries or wp-config entries (minus credentials–please!) for us to have a look at if you’d like.